Electric switch



R. K. MASON ELECTRIC SWITCH Filed July 13 192] Patented Dec. 2, 1924.

f UNITED STATES RALPH 1:. Mason, or BANTAM, connnc'rrour.

E EcrnIc swr'rcn.

Application filed July 13', 1921. Serial No. 484,415.

To all whom it may concern:

Be it known that I, RALPH K.-MAsoN,

a citizen of the United States, residing at- Bantam, in the county of Litchfield and State-of Connecticut, have invented certain new and useful Improvements in Electric Switches; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled intheart to which it appertains to make and use the same. i This inventionrelates to electric switches, particularly those which are intended for use in an enclosing casing." In switches'of this type, slight imperfections in manufacture and assembly, swelling or shrinkage of the blade connecting yoke bar, and numerous other factors often prevent'the switch blades from properly engaging the contacts in the casing, and furthermore the yoke bar is often'out of proper adjustment with rcspect to the switch operating mechanism within said casing. With the constructions usually employed, it is diflicult to overcome these factors, even imperfectly, but it is one object of the present invention to provide a structure whereby the blades and yoke bar may be minutely adjusted and tightly held in adjusted position, yet may be further adjusted should any circumstances arise which so require.

A further aim of the invention is to provide a construction which does not require drilling the blades and yoke bar to receive.

connecting fasteners, as is now commonly done. Consequently, the yoke bar is not weakened, the cross section of the blade is not reduced and its conductivity is not thereforelessened, and no'trouble is occasioned by alining holes in assembling the switch parts.

With the foregoing in view, the invention resides in the novel construction and combination of parts hereinafter described and claimed, the descriptive matter being supplemented by the accompanying drawing.

Figure 1 is a vertical sectional view of an enclosed switch embodying my invention.

Figure 2 is a vertical'sectional, view as indicated byline 22 of Fig. 1.

Figure 3 is a horizontal section taken on line 3-3 of Fig. 1.

Figure 4 is a side elevation ofone of the blanks of which the clamping yokes are formed.

scribed below.

Figure 5 is a longitudinal sectional view as indicated by line 55 of Fig. 4. I

Figure 6 is a perspective view of one of the :complete'yokes.

- In the drawings above briefly described,

the numeral 1 designates a casing having a suitable door 2 closing its front side. Within thecase 1, I have shown an insulated base 3 carryin 'fuseclips 4, pivoted switch blades 5' and fixed contacts-6 for co-action with said blades. The switch blades-5 are connected to the end portions of the yokebar 7 formed of fibre or other insulating material, and the bar 7 carries a forked arm 8 co-a'cting with acranked operating shaft 9 which extends across the casing 1, the outer end of said'shaft being equipped with a suitable handle 10.

The general construction above described is quite commonand no claim is based thereon except in association with the improvement set forth herein. It is obvious that if the switch blades 5 are not secured to the bar 7 in exactly the proper spaced relation, they will -'not accurately engage with the fixed contacts 6. It can also be seen that unless the yoke bar 7 is properly adjusted with respect to the cranked operating shaft, the 'SWltQh cannot be smoothly and easily operated. Hence, it is highly desirable to provide 35 means for so securing the yoke bar and blades together as to permit the necessary relative adjustment to be made, both when assembling the switch parts and at any future time, should further adjustment be necessary, due for instance to excessive shrinkage or swelling of the yoke bar 7. The preferred construction for meeting these de mands in an expeditious manner, I have de- From a singlelength of appro riate flat metal [such as that indicated in ig. '4, I stamp a U-shaped yoke- 12 having longitudinal slots 13 in its parallel arms and a tapped boss 14 at its central portion, said boss rev ceiving a clamping screw 15. One of the okes 12 straddles each end of the yoke bar 7 and the switch blades 5 pass through the slots 13, the proportion of parts being such that said yoke bar 7 may contact with the done, the. lades are moved into engagement with the contacts 6 and the yoke bar, 7 is properly adjusted with respect to the switch operating. mechanism, these adjustments being permitted by free sliding of the yokes 12 in either direction along the switch blades and yoke bar. The proper adjustments having been accurately made, the screws 15 are tightened and the parts? and 5 are thus frictionally clamped in rigid operative relation with each other, insuring perfect operation of the switch. If, in case of excessive swelling or shrinkage of thewfibre or other material of which the yoke ban? is constructed, the blades 5 assume positions other than those essential for eiiective engagement with the contacts 6, the necessary readjustments may be made by loosening the screws 15, resetting the parts as may be necessary, and againtightening said screws.

From the foregoing, taken in connection with the accompanying drawing, it will be seen that I have provided an extremely simple and inexpensive arrangement of parts for carrying out the objects of the invention, and that my invention is highly advantageousand in every way desirable. Since excellent results have been obtained from the details disclosed, they may well be followed, but I wish it understood that within the scope of the invention as claimed, numerous changes may be made. For instance, while I have shown and described a stamped metal construction for the yokes 12, it is to be understood that they may be cast or otherwise formed if desired. Furthermore, it is to be understood that my invention is not restricted to switches of the exact construction herein disclosed.

I claim: .A switch comprisinga plurality of parallel pivoted blades, stationary'contacts with which said blades coact, an insulating bar extending across said blades, operating means connected with said bar, and connecting means between said bar and blades ad,- justable along the latterto properly set said bar with respect to said operating means and adjustable along said bar to properly space said blades for true engagement with said contacts.

Intestimony whereof I have hereunto set my hand. y l

RALPH K. MASON. 

